Biomedical subjects

W C Heindel

Publications and source records attributed to W C Heindel.

22 records · Page 2Linked to original sources

PubMedDate not supplied

Retrograde amnesia in patients with Alzheimer's disease or Huntington's disease.

Retrograde amnesia (RA) was studied in patients with Huntington's disease (HD) or Alzheimer's disease (AD) using an updated version of the remote memory battery originally developed by Albert, Butters and Levin. Regardless of whether remote memory was measured by unaided recall or cued recall, HD patients exhibited deficits that were equally severe across decades. RA was more severe in AD than in HD patients and the AD patients recalled significantly more items from the 1940s and 50s than from the 60s, 70s or 80s. The AD patients also displayed dysnomia, while the HD patients did not. Naming difficulties appeared to contribute to the poor overall performance of the AD patients, but did not account for the temporal gradient of their RA. These findings, like recent reports focusing on these patients' ability to learn new information and to search semantic memory, indicate that the processes underlying AD and HD patients' memory failures are distinct.

Adult↗

PubMedDate not supplied

A single-photon emission computed tomography imaging study of driving impairment in patients with Alzheimer's disease.

Single-photon emission computed tomography (SPECT) was used in this study to examine the neurophysiologic basis of driving impairment in 79 subjects with dementia. Driving impairment, as measured by caregiver ratings, was significantly related to regional reduction of right hemisphere cortical perfusion on SPECT, particularly in the temporo-occipital area. With increased severity of driving impairment, frontal cortical perfusion was also reduced. Clock drawing was more significantly related to driving impairment than the Mini-Mental State Examination (MMSE). Driving impairment in Alzheimer's disease is related to changes in cortical function which vary according to the severity of the disease. Cognitive tests of visuoperceptual and executive functions may be more useful screening tools for identifying those at greatest risk for driving problems than examinations like the MMSE that are weighted toward left-hemisphere-based verbal tasks.

Activities of Daily Living↗

PubMedDate not supplied

Lateralized cortical perfusion in women with Alzheimer's disease.

OBJECTIVE: To define the pathophysiologic substrate of gender differences in cognition and behavior in Alzheimer's disease (AD). DESIGN: Hemispheric regional cerebral blood flow (rCBF) was studied in a consecutive series of dementia patients using single photon emission computed tomography (SPECT). PARTICIPANTS: Subjects included 300 outpatients who were studied with SPECT as part of a diagnostic evaluation for degenerative dementia or memory disorder. METHOD: Based on qualitative descriptions by a radiologist, subjects were classified as having unilateral left, unilateral right, bilateral, or no perfusion defects. Semiquantitative analysis of SPECT images was also performed using region of interest radionuclide counts normalized to the cerebellum. RESULTS: Among 174 females and 126 males, unilateral left hemisphere defects were found more commonly in women than men (24% vs 10%; chi 2 = 9.4; P = .009). This observation was most significant for the 103 females and 62 males regarded as having probable AD (26% vs 8%; chi 2 = 9.3; P = .01). In a multiple regression model of clinical variables, shorter duration of disease and female gender were significant independent predictors of the unilateral left hemisphere pattern among those with probable AD. Age, family history, education, handedness, and severity of cognitive impairment were not significant contributors. CONCLUSIONS: Women with AD exhibit greater heterogeneity in rCBF than men. Asymmetry in rCBF occurs more often in women. In some cases, this is related to relative preservation of right hemisphere function in women.

Aged↗

PubMedDate not supplied

Specificity of the memory deficits associated with basal ganglia dysfunction.

Recent studies comparing the explicit and implicit memory disorders of Huntington's disease (HD) and Alzheimer's disease (AD) patients have yielded new insights into the specificity of the memory disorders associated with basal ganglia dysfunction. Patients with HD have severe deficiencies in retrieving information from either episodic or semantic explicit memory. This retrieval deficit is not confounded by impairments in storage, rapid forgetting, intrusion errors and a deterioration of the structure of semantic knowledge. While HD patients perform normally on implicit memory tasks involving lexical, semantic and pictorial priming, they are impaired on implicit tests which require the initiation and/or modification of central motor programs. It is concluded that the basal ganglia play a specific but important role in memory although the processes they mediate are different from those dependent on the integrity of the hippocampus and diencephalon.

Basal Ganglia Diseases↗